Define execfile, file, long, raw_input, xrange for Python 3

samples/python/tutorial_code/core/AddingImages/adding_images.py

@@ -1,35 +1,36 @@
 from __future__ import print_function
-import sys
 
 import cv2 as cv
 
 alpha = 0.5
 
+try:
+    raw_input          # Python 2
+except NameError:
+    raw_input = input  # Python 3
+
 print(''' Simple Linear Blender
 -----------------------
 * Enter alpha [0.0-1.0]: ''')
-if sys.version_info >= (3, 0): # If Python 3.x
-    input_alpha = float(input())
-else:
-    input_alpha = float(raw_input())
+input_alpha = float(raw_input().strip())
 if 0 <= alpha <= 1:
     alpha = input_alpha
-## [load]
+# [load]
 src1 = cv.imread('../../../../data/LinuxLogo.jpg')
 src2 = cv.imread('../../../../data/WindowsLogo.jpg')
-## [load]
+# [load]
 if src1 is None:
-    print ("Error loading src1")
+    print("Error loading src1")
     exit(-1)
 elif src2 is None:
-    print ("Error loading src2")
+    print("Error loading src2")
     exit(-1)
-## [blend_images]
+# [blend_images]
 beta = (1.0 - alpha)
 dst = cv.addWeighted(src1, alpha, src2, beta, 0.0)
-## [blend_images]
-## [display]
+# [blend_images]
+# [display]
 cv.imshow('dst', dst)
 cv.waitKey(0)
-## [display]
+# [display]
 cv.destroyAllWindows()